Abstract. The study of vegetation dynamics in tallgrass prairie in response to fire has focused on dormant season fire in late successional prairies. Our objective was to determine if late season fire of varying frequency results in divergent successional patterns in an early successional tallgrass prairie disturbed by grazing and cultivation. Specifically, we evaluated the influence of late‐summer fires of varying frequency on community composition and species richness. We collected vegetation and environmental data on two sites burned in the late growing‐season at varying frequencies. These communities differed in composition depending primarily on edaphic factors, time since the last burn, and year‐to‐year variation. We interpret the time effect as related to changes in species composition accompanying plant succession that followed disturbance either from cropping and heavy grazing on the loamy site or heavy grazing on the shallow site. Other unidentified factors also have a role in vegetation dynamics on this prairie. Community composition and species richness were not consistently responsive to frequency of growing‐season fires.

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Growth response and nutrient levels in the foliage and growth medium were compared using Nephrolepsis exaltata (L.) Schott 'Compacta' ferns grown in a peat-perlite medium with 4 rates of dolomitic limestone (0.0, 1.2, 2.4, and 6.0 kg/m 3 ) and 2 rates of gypsum (0.0 and 1.2 kg/m 3 ). Incorporation of dolomitic limestone and gypsum resulted in greater growth compared to treatments without dolomitic limestone and gypsum, but dolomitic limestone rates of 1.2, 2.4, or 6.0 kg/m 3 resulted in no difference in fern dry weight. Addition of gypsum resulted in higher foliar S levels.Suppressed fern growth was associated with lower foliar Ca and S 65

Daconil 2787 4.17F and 75W (chlorothalonil) controlled leaf spot on photinia (Photinia fraseri) caused by Entomosporium maculatum in 2 tests under commercial nursery conditions. Manzate 200 80W (mancozeb) and Bordeaux mixture significantly reduced incidence and severity of the disease, but Benlate 50W (benomyl), Zyban 75W (thiophanate methyl + mancozeb), and Bayleton 50W (triadimefon) did not satisfactorily control Entomosporium leaf spot on photinia.

Postemergence applications of 1.1 and 0.6 kg/ha of sethoxydim (2-[l-ethoxyimino) butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-l-one) and fluazifop-butyl (butyl 2-[4-(5-trifluoromethyl-2-pyridyloxy)-phenoxy]propionate), respectively, resulted in 90% control of common bermudagrass (Cynodon dactylon) when applied directly over field-grown ornamentals. Comparable control was achieved by either single application or 2, half-rate, split applications. Of the 12 species tested, only ‘Hexe’ azalea was damaged by applications of fluazifop-butyl to a degree that the plants were unsaleable. All other species exhibited tolerance to both sethoxydim and fluazifop-butyl at the rates required to achieve grass control.